Okay, we are tasked with adding 6455 and 2507. Let's begin!

Step 1: We'll start by adding the digits 5 & 7 in column 1 and get 12.
We'll write down the last digit 2 and carry the 1 to the next column.

Step 2: We'll start by adding the digits 5 & 0 in column 2 and get 6.

Step 3: We'll start by adding the digits 4 & 5 in column 3 and get 9.

Step 4: We'll start by adding the digits 6 & 2 in column 4 and get 8.

So, 6455 + 2507 = 8962.

